Replying late. this is how I did it.
Works with parallel request as well.
import { HttpInterceptor, HttpRequest, HttpHandler, HttpErrorResponse, HttpEvent, HttpResponse } from '@angular/common/http';
import { Injectable } from '@angular/core';
import { environment } from 'src/environments/environment';
import { GlobalService } from './global.service';
import { tap, mergeMap, switchMap, filter, take, flatMap, catchError } from 'rxjs/operators';
import { Observable, Subject, throwError, of, BehaviorSubject } from 'rxjs';
@Injectable()
export class InterceptorService implements HttpInterceptor {
private isRefreshing = false;
private refreshTokenSubject: BehaviorSubject<any> = new BehaviorSubject<any>(null);
constructor(public globalService: GlobalService) {
}
intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
request = this.addHeader(request);
// console.log('request ', request);
return next.handle(request).pipe(catchError((error: any) => {
if (error instanceof HttpErrorResponse) {
if (error.status === 401) {
if (!this.isRefreshing) {
this.isRefreshing = true;
this.refreshTokenSubject.next(null);
request = this.addHeader(request);
console.log('Token request');
return this.globalService.getRefershToken().pipe(
switchMap((token: any) => {
console.log('inside token');
this.isRefreshing = false;
if (token && token.access_token && token.refresh_token) {
sessionStorage.setItem('accessToken', token.access_token);
sessionStorage.setItem('refreshToken', token.refresh_token);
}
// request = this.addHeader(request);
// console.log('request: ', request);
this.refreshTokenSubject.next(token);
return next.handle(this.addHeader(request));
}));
} else {
console.log('inside else call');
console.log('token : ', this.refreshTokenSubject.getValue());
return this.refreshTokenSubject.pipe(
filter(token => (token != null && token != undefined)),
take(1),
switchMap(() => {
console.log('adding header in else');
return next.handle(this.addHeader(request))
}));
}
}
}
}));
}
private addHeader(request: HttpRequest<any>) {
let getEndPoint = request.url.split('/')[request.url.split('/').length - 1];
if (getEndPoint !== 'refreshToken') {
const accessToken = sessionStorage.getItem('accessToken');
request = request.clone({
setHeaders: {
Authorization: `Bearer ${accessToken}`
}
});
} else if (getEndPoint === 'refreshToken') {
const refreshToken = sessionStorage.getItem('refreshToken');
request = request.clone({
setHeaders: {
applicationCode: environment.applicationCode,
'refresh-token': `${refreshToken}`,
}
});
}
return request;
}
}